| Summary: | Coals of Cretaceous age are preserved within the fill of several Australian sedimentary basins. Presently, Cretaceous coal is mined in only one area, although numerous coalfields have been active over the past century. Cretaceous organic facies in the subsurface of the Gippsland Basin, offshore southeast Australia, are thought to have sourced the major oil and gas accumulations of that area. Cretaceous coal-bearing basins in Australia fall into four groups: 1. interior basins, notably the Eromanga Basin where the greatest occurrence of coal is in the Cenomanian Winton Formation; 2. east coast basins, including the Laura Basin (Late Jurassic to Early Cretaceous Battle Camp Formation), Styx Basin (Albiah to Cenomanian Styx Coal Measures), Stanwell Outlier (Albian Stanwell Coal Measures), and Maryborough Basin (Albian Burrum Coal Measures); 3. south coast basins, notably the Great Australian Bight, Otway Basin (Otway and Sherbrook Groups), Bass Basin, (Otway and Eastern View Groups), and Gippsland Basin (Strzelecki and Latrobe Groups), where coal is known from throughout the Cretaceous system; 4. west coast basins, notably the Perth Basin, which contains minor, Early Cretaceous coal. The major control on the formation and distribution of Cretaceous coal in Australia was the development of widespread, rapidly-subsiding lowland environments during passive margin breakup between Australia and Antarctica, and between Australia and Lord Howe Rise. The widespread stratigraphic distribution of coal resources suggests that fluctuating climate and evolving vegetational communities did not fundamentally affect coal development. The role of eustatic sea-level changes is difficult to assess at present. Within individual basins, structural regime and the distribution of depositional systems also played an active role in controlling coal distribution.
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